Polymer composites comprising low molecular weight nitrile rubber

1. A polymer composite comprising at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) below 30 and a polydispersity below 2.7 at least one filler and optionally at least one cross-linking agent,

wherein the optionally hydrogenated, nitrile rubber polymer is prepared by reacting a nitrile polymer in the presence of one ore more compounds of the general formulas I, II, III or IV;

wherein:

M is Os or Ru,

R and R 1 are, independently, hydrogen or a hydrocarbon selected from the group consisting of C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, C 1 -C 20 alkyl, aryl, C 1 -C 20 carboxylate, C 1 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C 2 -C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkylthio, C 1 -C 20 alkylsulfonyl and C 1 -C 20 alkylsulfinyl,

X and X 1 are independently any anionic ligand, and

L and L 1 are independently any neutral ligand;

wherein:

M 1 is Os or Ru;

R 2 and R 3 are, independently, hydrogen or a hydrocarbon selected from the group consisting of C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, C 1 -C 20 alkyl, aryl, C 1 -C 20 carboxylate, C 1 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C 2 -C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkylthio, C 1 -C 20 alkylsulfonyl and C 1 -C 20 alkylsulfinyl,

X 2 is an anionic ligand, and

L 2 is a neutral π-bonded ligand, independent of whether it is mono- or polycyclic,

L 3 is a ligand selected from the group consisting of phosphines, sulfonated phosphines, fluorinated phosphines, functionalized phosphines bearing up to three aminoalkyl-, ammoniumalkyl-, alkoxyalkyl-, alkoxylcarbonylalkyl-, hydrocycarbonylalkyl-, hydroxyalkyl- or ketoalkyl- groups, phosphites, phosphinites, phosphonites, phosphinamines, arsines, stibenes, ethers, amines, amides, imines, sulfoxides, thioethers and pyridines,

Y′ is a non-coordinating anion,

n is an integer in the range of from 0 to 5;

wherein

M 2 is Mo or W,

R 4 and R 5 are, independently, hydrogen or a hydrocarbon selected from the group consisting of C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, C 1 -C 20 alkyl, aryl, C 1 -C 20 carboxylate, C 1 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C2-C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkythio, C 1 -C 20 alkylsulfonyl and C 1 -C 20 alkylsulfinyl,

R 6 and R 7 are independently selected from any unsubstituted or halo-substituted alkyl, aryl, aralkyl groups or silicon-containing analogs thereof,

wherein:

M is Os or Ru,

R and R 1 are independently selected from the group consisting of hydrogen, substituted or unsubstituted alkyl, and substituted or unsubstituted alkyl,

X and X 1 are independently any anionic ligand, and

L and L 1 are independently any neutral ligand.

2. The polymer composite according to claim 1 , wherein the polymer Mooney viscosity (ML 1+4 @ 100° C.) is below 20.

3. The polymer composite according to claim 1 , wherein the polymer Mooney viscosity (ML 1+4 @ 100° C.) is below 10.

4. The polymer composite according to claim 1 , wherein the polymer composite further comprises a curing system selected from the group consisting of peroxide curing systems and sulfur curing systems.

5. A process for preparing the polymer composite according to claim 1 , comprising mixing at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) below 30, at least one filler and optionally at least one cross-linking agent.

6. A process for the manufacture of a shaped article comprising the step of injection molding the polymer composite according to claim 1 , comprising at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) below 30 and a polydispersity index below 2.7, at least one filler and at least one cross-linking agent.

7. A process according to claim 6 , wherein the shaped article is seal, gasket, belt, hose, bearing pad, stator, well head seal, valve plate, cable sheathing, wheel, roller, in place gaskets or pipe seal.

8. The process for the manufacture of a shaped article comprising the step of liquid injection molding the polymer composite according to claim 1 , comprising at least one, optionally hydrogenated, nitrite rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) below 10, at least one filler and at least one cross-linking agent.

9. The process according to claim 8 , wherein the shaped article is seal, gasket, belt, hose, bearing pad, stator, well head seal, valve plate. cable sheathing, wheel, roller, in place gaskets or pipe seal.

10. The process according to claim 1 , wherein natural ligands L and L 1 are selected from the group consisting of phosphines, amines, thioethers, imidazolidinylidenes and any neutral carbine.

11. The process according to claim 1 , wherein L and L 1 are linked to one another to from a bidentate neutral ligand.